Nimbus Manticore Deploys NightLedger and Turns Victim Systems Into Covert Relays Ravie Lakshmanan Jul 28, 2026 Malware / Cyber Espionage The Iranian state-backed hacking group tracked as Nimbus Manticore (aka GalaxyGato, Mirage Kitten, Smoke Sandstorm, Subtle Snail, and UNC1549) has been attributed to a fresh set of attacks targeting entities across the Middle East, Africa, and South Asia. The intrusions involve the use of a previously undocumented Windows backdoor called NightLedger and two custom WebSocket tunnelers, BridgeHead and ArcBridge, with an aim to maintain covert access. Targets of the campaign include Egypt, SMB and government environments in Jordan and Tanzania, aviation organizations in Pakistan, telecommunication companies in Ethiopia, and financial-sector entities in Burkina Faso, per Kaspersky. "The toolset includes NightLedger, a new Windows backdoor for reconnaissance, command execution, file operations, process discovery, and screenshot capture; and two custom WebSocket-based tunnelers, ArcBridge and BridgeHead, for covert network access and operator-controlled tunneling," Kaspersky researchers Omar Amin and Vasily Berdnikov said . The exact initial access method used in the attacks is presently unknown, although the adversary is known to employ highly tailored job opportunity-themed phishing lures masquerading as trusted brands and hiring platforms, as well as lookalike videoconferencing pages, to redirect recipients to malicious archives hosted on third-party file-sharing services. The as-yet-undetermined access route is then abused to deliver the malicious payloads, including NightLedger, which is launched as a DLL via DLL side-loading. The malware is designed to contact an external server over HTTPS to parse and run commands in a manner that's analogous to TWOSTROKE , another backdoor deployed by the threat actor in the past. The list of supported commands is below - Gather user and host identity information Execute a process/program List directories Download a file to the infected system Collect host and network information Copy or delete files Update beacon interval Take a screenshot Load a DLL Terminate a process or thread Upload file to the command-and-control (C2) server via an HTTP POST request Enumerate logical drives List processes Collect C:\Windows\debug\NetSetup.log (a diagnostic file used for troubleshooting domain join issues) together with process-list output Two other malware families delivered as part of the attacks are BridgeHead ("unbcl.dll"), a SOCKS5 tunnel proxy observed in environments in Egypt and Pakistan that shares some level of functional overlaps with MiniFast (aka MiniUpdate and Retrograde), and ArcBridge, another WebSocket tunneling tool observed in April 2026 in activity targeting victims in the Middle East. "The C2 server initiates all tunnel connections by sending binary commands over the WebSocket; the implant simply forwards traffic between server-specified targets and the WebSocket channel," the researchers said about BridgeHead. "This makes it a relay node: the operator runs tools server-side, and all resulting TCP traffic is tunneled through the victim's machine as if originating from the victim's network." The use of BridgeHead and ArcBridge indicates the threat actor's continued use of tunneling utilities, which has been previously observed relying on bespoke tunnelers such as LIGHTRAIL and POLLBLEND . The disclosure comes days after Group-IB uncovered a new malware sample codenamed HOLLOWGRAPH that's linked to the Cavern (aka Cav3rn) framework used by an Iranian hacking crew dubbed Cavern Manticore . "HOLLOWGRAPH abuses Microsoft Graph API to transform a compromised Microsoft 365 calendar into a covert two-way command-and-control channel," it said. "Using the Microsoft Graph API, it treats the compromised mailbox's calendar as a two-way dead-drop: operators plant tasking as calendar events, and the implant exfiltrates stolen files by creating its own events with encrypted data attached. To avoid catching the mailbox owner's attention, every event is dated far into the future - 13 May 2050 - with payloads attached as files to the event." Found this article interesting? Follow us on Google News , Twitter and LinkedIn to read more exclusive content we post. SHARE Tweet Share Share Share Share on Facebook Share on Twitter Share on Linkedin Share on Reddit Share on Hacker News Share on Email Share on WhatsApp Share on Facebook Messenger Share on Telegram SHARE Cloud security , critical infrastructure , cyber espionage , Malware , network security , Phishing , Threat Intelligence , Windows Security ⚡ Top Stories This Week New Bit2Watt Attack Could Let Cloud Tenants Disrupt Power Grids Without an Exploit Open-Source Android AI Agents Could Let Invisible Screen Text Run Code on Host PCs Critical SharePoint RCE CVE-2026-50522 Under Active Exploitation After Public PoC AWS Kiro Flaw Let a Poisoned Web Page Rewrite Its Config and Run Code Apple Fixes Hide My Email Bug That Exposed Real Addresses in Mail Logs Microsoft Azure DevOps MCP Flaw Lets Hidden PR Comments Hijack AI Review Agents OpenAI Says Its AI Models Escaped Sandbox, Targeted Hugging Face to Cheat Benchmark Adobe Acrobat Extension Flaw Let Malicious Sites Read WhatsApp Web Data Ubuntu snap-confine Flaw Could Give Local Users Root on Default Desktop Installs Nine-Year-Old RefluXFS Linux Flaw Gives Local Users Root on Default RHEL Installs Attackers Weaponize GitHub Actions Runners to Target cPanel and WHM Servers Claude Cowork Flaw Could Let AI Agent Escape Its VM and Access Mac Files ThreatsDay: Android Spyware, PLC Attacks, AI Image Prompt Injection + 12 More Stories Kimi K3 Agents Found Redis Zero-Days and Built RCE Exploit, Researchers Say Hacker Runs Hermes AI Agent Unattended for Post-Exploitation at Thai Finance Ministry ChatGPT AgentForger Flaw Could Deploy Rogue Workspace Agents via a Phishing Link Certighost Exploit Lets Low-Privileged Active Directory Users Impersonate a Domain Controller Researcher Publishes GitLab RCE PoC Letting Authenticated Users Run Commands as Git Fastjson 1.x RCE Vulnerability Targeted in Attacks With No Patched Available Malvertising Sends Malware in Pieces, Then Makes the Browser Build the Executable ⭐ Featured Resources Identity Fraud Is Changing Fast. See the Attacks Businesses Face in 2026 What 25 Million Alerts Reveal About the Threats SOCs Ignore How to Find and Control Every Script Running Through Your Marketing Stack Modern SASE Guide: Close the Gaps Traditional Network Security Cannot See